Merge bitcoin#28583: refactor: [tidy] modernize-use-emplace

fa05a72 tidy: modernize-use-emplace (MarcoFalke)

Pull request description:

  Constructing a temporary unnamed object only to copy or move it into a container seems both verbose in code and a strict performance penalty.

  Fix both issues via the `modernize-use-emplace` tidy check.

ACKs for top commit:
  Sjors:
    re-utACK fa05a72
  hebasto:
    ACK fa05a72.
  TheCharlatan:
    ACK fa05a72

Tree-SHA512: 4408a094f406e7bf6c1468c2b0798f68f4d952a1253cf5b20bdc648ad7eea4a2c070051fed46d66fd37bce2ce6f85962484a1d32826b7ab8c9baba431eaa2765

Author: fanquake

src/.bear-tidy-config

@@ -12,6 +12,8 @@
         "src/leveldb",
         "src/minisketch",
         "src/univalue",
+        "src/bench/nanobench.cpp",
+        "src/bench/nanobench.h",
         "src/secp256k1"
       ]
     },

src/.clang-tidy

@@ -4,6 +4,7 @@ bugprone-argument-comment,
 bugprone-use-after-move,
 misc-unused-using-decls,
 modernize-use-default-member-init,
+modernize-use-emplace,
 modernize-use-nullptr,
 performance-for-range-copy,
 performance-move-const-arg,

src/bench/wallet_loading.cpp

@@ -46,8 +46,8 @@ static void BenchUnloadWallet(std::shared_ptr<CWallet>&& wallet)
 static void AddTx(CWallet& wallet)
 {
     CMutableTransaction mtx;
-    mtx.vout.push_back({COIN, GetScriptForDestination(*Assert(wallet.GetNewDestination("")))});
-    mtx.vin.push_back(CTxIn());
+    mtx.vout.emplace_back(COIN, GetScriptForDestination(*Assert(wallet.GetNewDestination(""))));
+    mtx.vin.emplace_back();
 
     wallet.AddToWallet(MakeTransactionRef(mtx), TxStateInactive{});
 }

src/external_signer.cpp

@@ -54,7 +54,7 @@ bool ExternalSigner::Enumerate(const std::string& command, std::vector<ExternalS
         if (model_field.isStr() && model_field.getValStr() != "") {
             name += model_field.getValStr();
         }
-        signers.push_back(ExternalSigner(command, chain, fingerprintStr, name));
+        signers.emplace_back(command, chain, fingerprintStr, name);
     }
     return true;
 }

src/httpserver.cpp

@@ -177,8 +177,8 @@ static bool ClientAllowed(const CNetAddr& netaddr)
 static bool InitHTTPAllowList()
 {
     rpc_allow_subnets.clear();
-    rpc_allow_subnets.push_back(CSubNet{LookupHost("127.0.0.1", false).value(), 8});  // always allow IPv4 local subnet
-    rpc_allow_subnets.push_back(CSubNet{LookupHost("::1", false).value()});  // always allow IPv6 localhost
+    rpc_allow_subnets.emplace_back(LookupHost("127.0.0.1", false).value(), 8);  // always allow IPv4 local subnet
+    rpc_allow_subnets.emplace_back(LookupHost("::1", false).value());  // always allow IPv6 localhost
     for (const std::string& strAllow : gArgs.GetArgs("-rpcallowip")) {
         const CSubNet subnet{LookupSubNet(strAllow)};
         if (!subnet.IsValid()) {
@@ -330,8 +330,8 @@ static bool HTTPBindAddresses(struct evhttp* http)
 
     // Determine what addresses to bind to
     if (!(gArgs.IsArgSet("-rpcallowip") && gArgs.IsArgSet("-rpcbind"))) { // Default to loopback if not allowing external IPs
-        endpoints.push_back(std::make_pair("::1", http_port));
-        endpoints.push_back(std::make_pair("127.0.0.1", http_port));
+        endpoints.emplace_back("::1", http_port);
+        endpoints.emplace_back("127.0.0.1", http_port);
         if (gArgs.IsArgSet("-rpcallowip")) {
             LogPrintf("WARNING: option -rpcallowip was specified without -rpcbind; this doesn't usually make sense\n");
         }
@@ -343,7 +343,7 @@ static bool HTTPBindAddresses(struct evhttp* http)
             uint16_t port{http_port};
             std::string host;
             SplitHostPort(strRPCBind, port, host);
-            endpoints.push_back(std::make_pair(host, port));
+            endpoints.emplace_back(host, port);
         }
     } else { // No specific bind address specified, bind to any
         endpoints.push_back(std::make_pair("::", http_port));
@@ -706,7 +706,7 @@ void RegisterHTTPHandler(const std::string &prefix, bool exactMatch, const HTTPR
 {
     LogPrint(BCLog::HTTP, "Registering HTTP handler for %s (exactmatch %d)\n", prefix, exactMatch);
     LOCK(g_httppathhandlers_mutex);
-    pathHandlers.push_back(HTTPPathHandler(prefix, exactMatch, handler));
+    pathHandlers.emplace_back(prefix, exactMatch, handler);
 }
 
 void UnregisterHTTPHandler(const std::string &prefix, bool exactMatch)

src/net_permissions.cpp

@@ -71,13 +71,13 @@ bool TryParsePermissionFlags(const std::string& str, NetPermissionFlags& output,
 std::vector<std::string> NetPermissions::ToStrings(NetPermissionFlags flags)
 {
     std::vector<std::string> strings;
-    if (NetPermissions::HasFlag(flags, NetPermissionFlags::BloomFilter)) strings.push_back("bloomfilter");
-    if (NetPermissions::HasFlag(flags, NetPermissionFlags::NoBan)) strings.push_back("noban");
-    if (NetPermissions::HasFlag(flags, NetPermissionFlags::ForceRelay)) strings.push_back("forcerelay");
-    if (NetPermissions::HasFlag(flags, NetPermissionFlags::Relay)) strings.push_back("relay");
-    if (NetPermissions::HasFlag(flags, NetPermissionFlags::Mempool)) strings.push_back("mempool");
-    if (NetPermissions::HasFlag(flags, NetPermissionFlags::Download)) strings.push_back("download");
-    if (NetPermissions::HasFlag(flags, NetPermissionFlags::Addr)) strings.push_back("addr");
+    if (NetPermissions::HasFlag(flags, NetPermissionFlags::BloomFilter)) strings.emplace_back("bloomfilter");
+    if (NetPermissions::HasFlag(flags, NetPermissionFlags::NoBan)) strings.emplace_back("noban");
+    if (NetPermissions::HasFlag(flags, NetPermissionFlags::ForceRelay)) strings.emplace_back("forcerelay");
+    if (NetPermissions::HasFlag(flags, NetPermissionFlags::Relay)) strings.emplace_back("relay");
+    if (NetPermissions::HasFlag(flags, NetPermissionFlags::Mempool)) strings.emplace_back("mempool");
+    if (NetPermissions::HasFlag(flags, NetPermissionFlags::Download)) strings.emplace_back("download");
+    if (NetPermissions::HasFlag(flags, NetPermissionFlags::Addr)) strings.emplace_back("addr");
     return strings;
 }
 

src/net_processing.cpp

@@ -2799,7 +2799,7 @@ void PeerManagerImpl::ProcessGetBlockData(CNode& pfrom, Peer& peer, const CInv&
             // and we want it right after the last block so they don't
             // wait for other stuff first.
             std::vector<CInv> vInv;
-            vInv.push_back(CInv(MSG_BLOCK, m_chainman.ActiveChain().Tip()->GetBlockHash()));
+            vInv.emplace_back(MSG_BLOCK, m_chainman.ActiveChain().Tip()->GetBlockHash());
             m_connman.PushMessage(&pfrom, msgMaker.Make(NetMsgType::INV, vInv));
             peer.m_continuation_block.SetNull();
         }
@@ -3199,7 +3199,7 @@ void PeerManagerImpl::HeadersDirectFetchBlocks(CNode& pfrom, const Peer& peer, c
                     // Can't download any more from this peer
                     break;
                 }
-                vGetData.push_back(CInv(MSG_BLOCK, pindex->GetBlockHash()));
+                vGetData.emplace_back(MSG_BLOCK, pindex->GetBlockHash());
                 BlockRequested(pfrom.GetId(), *pindex);
                 LogPrint(BCLog::NET, "Requesting block %s from  peer=%d\n",
                         pindex->GetBlockHash().ToString(), pfrom.GetId());
@@ -4616,7 +4616,7 @@ void PeerManagerImpl::ProcessMessage(
         const auto send_headers = [this /* for m_connman */, &hashStop, &pindex, &nodestate, &pfrom, &msgMaker](auto msg_type_internal, auto& v_headers, auto callback) {
             int nLimit = GetHeadersLimit(pfrom, msg_type_internal == NetMsgType::HEADERS2);
             for (; pindex; pindex = m_chainman.ActiveChain().Next(pindex)) {
-                v_headers.push_back(callback(pindex));
+                v_headers.emplace_back(callback(pindex));
 
                 if (--nLimit <= 0 || pindex->GetBlockHash() == hashStop)
                     break;
@@ -6167,14 +6167,14 @@ bool PeerManagerImpl::SendMessages(CNode* pto)
                     }
                     if (fFoundStartingHeader) {
                         // add this to the headers message
-                        vHeaders.push_back(pindex->GetBlockHeader());
+                        vHeaders.emplace_back(pindex->GetBlockHeader());
                     } else if (PeerHasHeader(&state, pindex)) {
                         continue; // keep looking for the first new block
                     } else if (pindex->pprev == nullptr || PeerHasHeader(&state, pindex->pprev) || isPrevDevnetGenesisBlock) {
                         // Peer doesn't have this header but they do have the prior one.
                         // Start sending headers.
                         fFoundStartingHeader = true;
-                        vHeaders.push_back(pindex->GetBlockHeader());
+                        vHeaders.emplace_back(pindex->GetBlockHeader());
                     } else {
                         // Peer doesn't have this header or the prior one -- nothing will
                         // connect, so bail out.
@@ -6282,7 +6282,7 @@ bool PeerManagerImpl::SendMessages(CNode* pto)
 
             // Add blocks
             for (const uint256& hash : peer->m_blocks_for_inv_relay) {
-                vInv.push_back(CInv(MSG_BLOCK, hash));
+                vInv.emplace_back(MSG_BLOCK, hash);
                 if (vInv.size() == MAX_INV_SZ) {
                     m_connman.PushMessage(pto, msgMaker.Make(NetMsgType::INV, vInv));
                     vInv.clear();
@@ -6527,7 +6527,7 @@ bool PeerManagerImpl::SendMessages(CNode* pto)
             NodeId staller = -1;
             FindNextBlocksToDownload(*peer, MAX_BLOCKS_IN_TRANSIT_PER_PEER - state.nBlocksInFlight, vToDownload, staller);
             for (const CBlockIndex *pindex : vToDownload) {
-                vGetData.push_back(CInv(MSG_BLOCK, pindex->GetBlockHash()));
+                vGetData.emplace_back(MSG_BLOCK, pindex->GetBlockHash());
                 BlockRequested(pto->GetId(), *pindex);
                 LogPrint(BCLog::NET, "Requesting block %s (%d) peer=%d\n", pindex->GetBlockHash().ToString(),
                     pindex->nHeight, pto->GetId());

src/node/blockstorage.cpp

@@ -331,7 +331,7 @@ bool BlockManager::WriteBlockIndexDB()
     std::vector<std::pair<int, const CBlockFileInfo*>> vFiles;
     vFiles.reserve(m_dirty_fileinfo.size());
     for (std::set<int>::iterator it = m_dirty_fileinfo.begin(); it != m_dirty_fileinfo.end();) {
-        vFiles.push_back(std::make_pair(*it, &m_blockfile_info[*it]));
+        vFiles.emplace_back(*it, &m_blockfile_info[*it]);
         m_dirty_fileinfo.erase(it++);
     }
     std::vector<const CBlockIndex*> vBlocks;

src/qt/rpcconsole.cpp

@@ -184,7 +184,7 @@ class PeerIdViewDelegate : public QStyledItemDelegate
 bool RPCConsole::RPCParseCommandLine(interfaces::Node* node, std::string &strResult, const std::string &strCommand, const bool fExecute, std::string * const pstrFilteredOut, const WalletModel* wallet_model)
 {
     std::vector< std::vector<std::string> > stack;
-    stack.push_back(std::vector<std::string>());
+    stack.emplace_back();
 
     enum CmdParseState
     {
@@ -212,7 +212,7 @@ bool RPCConsole::RPCParseCommandLine(interfaces::Node* node, std::string &strRes
         }
         // Make sure stack is not empty before adding something
         if (stack.empty()) {
-            stack.push_back(std::vector<std::string>());
+            stack.emplace_back();
         }
         stack.back().push_back(strArg);
     };
@@ -221,7 +221,7 @@ bool RPCConsole::RPCParseCommandLine(interfaces::Node* node, std::string &strRes
         if (nDepthInsideSensitive) {
             if (!--nDepthInsideSensitive) {
                 assert(filter_begin_pos);
-                filter_ranges.push_back(std::make_pair(filter_begin_pos, chpos));
+                filter_ranges.emplace_back(filter_begin_pos, chpos);
                 filter_begin_pos = 0;
             }
         }
@@ -321,7 +321,7 @@ bool RPCConsole::RPCParseCommandLine(interfaces::Node* node, std::string &strRes
                             if (nDepthInsideSensitive) {
                                 ++nDepthInsideSensitive;
                             }
-                            stack.push_back(std::vector<std::string>());
+                            stack.emplace_back();
                         }
 
                         // don't allow commands after executed commands on baselevel

src/rest.cpp

@@ -761,7 +761,7 @@ static bool rest_getutxos(const CoreContext& context, HTTPRequest* req, const st
                 return RESTERR(req, HTTP_BAD_REQUEST, "Parse error");
 
             txid.SetHex(strTxid);
-            vOutPoints.push_back(COutPoint(txid, (uint32_t)nOutput));
+            vOutPoints.emplace_back(txid, (uint32_t)nOutput);
         }
 
         if (vOutPoints.size() > 0)